Discussion

So after a lot of though i have finished my discussion... howeever, it's not too long. hopefully the quality-quantity thing works for me here...
The hypothesis was that a soil type with more porosity will have more space for the pollutant to fill and therefore it will absorb more of the pollutant. Sand has a porosity of 5-30%, sandstone (made up of sand) has a porosity of 55% and the porosity of potting mix is unknown. However, since the potting mix had coir dust in it, it can be assumed that it has a higher porosity than the typical soil found in a garden. If this is assumed, then the results from the experiment support the hypothesis and the experiment was successful as the aim of the experiment, to investigate which soil absorbs the greatest amount of pollutants in the environment, was fulfilled.
From the experiment, it was found that the potting mix absorbed the most amount of liquid in total, followed by the soil from the garden. The white sand absorbed the least. However, when it came to the experiments involving petrol, potting mix absorbed the least amount of the pollutant. It absorbed 26millilitres less than the white sand and 6 millilitres less than the soil from the garden. The reason for this is due to the pollutants’ viscosity. Viscosity is a liquid’s resistance to flow. A liquid that has a high viscosity will resist flowing more than a liquid that has a low viscosity. Oil has the highest viscosity out of the three pollutants followed by the diluted engine coolant. It was observed that the oil and engine coolant sat on top of the soils for a while when they had been poured on. This now can be concluded that this was because they both had higher viscosities. Petrol has a low viscosity; it has a lower viscosity than water. Potting mix is very porous and has very large void spaces, whereas the void spaces of the white sand and the soil from the garden are smaller and more compacted. This meant that the petrol passed through the potting mix much faster than it did for the white sand and the soil from the garden. After the 60 seconds had passed, the petrol may have only gotten half way through the white sand when it would have come through in the potting mix. Since the method used does not take into account the porosity of the pollutants, the method is not entirely reliable. However, the hypothesis can still be supported by the experiment as it still proves that a soil type with more porosity will absorb more of the pollutant.
well I think it's ok...i guess...